更新输入并触发观察者内的操作按钮

Question

我有一个应用程序，它利用 actionButton 将过滤器选择应用于绘图。该应用程序还包含一个重置 actionButton，它将下拉选择器重置为其原始值，在本例中为 mpg.

我想知道是否有可能让重置按钮不仅更新选择器本身，而且触发应用按钮，以便绘图恢复显示 mpg 作为 y-初始化时的轴值。

请注意，应用程序必须使用下面显示的 reactiveValues 构造，因为它存在于实际业务用例中。

library(shiny)
library(plotly)

ui <- fluidPage(
  ## input and output ui elements and apply/reset buttons
  selectInput("var", "Select Y-Axis Variable", c("mpg", "hp", "wt", "am")),
  actionButton("apply", "Apply"),
  actionButton("reset", "Reset"),
  plotlyOutput("plot")
)

server <- function(input, output, session) {
  ## stored default values
  plot_vals <- reactiveValues(y = "mpg")
  observeEvent(input$apply, {
    plot_vals$y <- input$var
  })
  ## render plot
  output$plot <- renderPlotly(
    mtcars %>% 
      plot_ly(x = ~disp,
              y = ~get(plot_vals$y),
              type = "scatter",
              mode = "markers")
  )
  ## update selectors (how can I have this segment not only update the drop down, but also trigger the apply button?)
  observeEvent(input$reset, {
    updateSelectInput(session = session, "var", selected = "mpg")
  })
}

shinyApp(ui, server)

Answer 1

只需在重置时更新 reactiveVal：

library(shiny)
library(plotly)

ui <- fluidPage(
  ## input and output ui elements and apply/reset buttons
  selectInput("var", "Select Y-Axis Variable", c("mpg", "hp", "wt", "am")),
  actionButton("apply", "Apply"),
  actionButton("reset", "Reset"),
  plotlyOutput("plot")
)

server <- function(input, output, session) {
  ## stored default values
  plot_vals <- reactiveValues(y = "mpg")
  observeEvent(input$apply, {
    plot_vals$y <- input$var
  })
  ## render plot
  output$plot <- renderPlotly({
    mtcars %>% 
      plot_ly(x = ~disp,
              y = ~get(plot_vals$y),
              type = "scatter",
              mode = "markers")
  })
  ## update selectors (how can I have this segment not only update the drop down, but also trigger the apply button?)
  observeEvent(input$reset, {
    updateSelectInput(session = session, "var", selected = "mpg")
    plot_vals$y <- "mpg"
  })
}

shinyApp(ui, server)

更新输入并触发观察者内的操作按钮

Updating an input and triggering an action button inside an observer

r

shiny